Pathogenic waste treatment

Abstract

Solid waste such as sewage sludge containing fecal matter is processed to reduce pathogens by at least 90% and converted to a useful product such as an amendment to agricultural land by combining the waste with an acid such as concentrated sulfuric and a base such as fly ash which exothermically react and thermally pasteurize the waste and add mineral value to the product. Pozzolanic materials, such as fly ash agglomerate the product and after grinding, the particles can aerate soil. The calcium oxide in fly ash reacts with sulfuric acid to form calcium sulfate dihydrate, a soil amendment. The amount of sulfuric acid can be controlled to provide a product with acid pH which is useful to neutralize alkaline soils such as those found in the Western United States of America.

We claim: 
     
       1. A product produced by the exothermic reaction of fecal-containing solid waste with an acid-base pair, said product containing no more than 10% of its original pathogen content. 
     
     
       2. A product according to claim 1 in which 15% of the product comprises the residue of fecal matter. 
     
     
       3. A product according to claim 2 in which the reaction product contains from 1 to 30% by weight of a pozzolanic agglomerating agent. 
     
     
       4. A product according to claim 3 in which the agglomerating agent is the residue of fly ash. 
     
     
       5. A product according to claim 4 in which the agglomerated product is subdivided into particulate form. 
     
     
       6. A product according to claim 5 containing at least 20% by weight of calcium sulfate. 
     
     
       7. A product according to claim 6 in which the pH is below 7. 
     
     
       8. A product according to claim 7 containing at least 5% by weight of at least one of nitrogen, phosphorous or potassium.